Perovskite light-emitting diode devices and display panels

Abstract

The present application discloses a perovskite light-emitting diode device and a display panel. The perovskite light-emitting diode device comprises a cathode layer, an anode layer and a functional layer arranged between the cathode layer and the anode layer; wherein the functional layer comprises a perovskite light-emitting layer and a hole injection layer, the hole injection layer is located between the perovskite light-emitting layer and the anode layer, and the material of the hole injection layer comprises a thiophene polymer and graphyne. The present application improves the hole injection performance of the perovskite light-emitting diode device, thereby improving the luminous efficiency of the perovskite light-emitting diode device.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a perovskite light emitting diode device and a display panel. Background Art

[0002] In recent years, through component optimization, interface modification, carrier transport layer optimization and structural design, the performance of light-emitting diodes based on perovskite materials has approached that of mature organic light-emitting diode devices and quantum dot light-emitting diode devices. The use of inkjet printing to prepare high-resolution perovskite optoelectronic devices is regarded as a powerful application of perovskite light-emitting diode devices.

[0003] The performance of perovskite light-emitting diode devices is related to the properties of the interface. In order to further improve the hole injection performance of perovskite light-emitting diode devices, it is usually necessary to match suitable and efficient hole injection materials. However, when existing hole injection materials such as PEDOT:PSS are used as materials for the hole injection layer, the hole injection performance of perovskite light-emitting diode devices is poor, which is not conducive to improving the luminous efficiency of perovskite light-emitting diode devices. Summary of the invention

[0004] The embodiments of the present application provide a perovskite light emitting diode device and a display panel to improve the hole injection performance of the perovskite light emitting diode device and improve the luminous efficiency of the perovskite light emitting diode device.

[0005] The present application provides a perovskite light-emitting diode device, which includes:

[0006] cathode layer;

[0007] an anode layer, disposed opposite to the cathode layer; and

[0008] A functional layer, disposed between the cathode layer and the anode layer;

[0009] The functional layer comprises a perovskite light-emitting layer and a hole injection layer, the hole injection layer is located between the perovskite light-emitting layer and the anode layer, and the material of the hole injection layer comprises thiophene polymer and graphyne.

[0010] Optionally, in some embodiments of the present application, the hole injection layer includes at least two hole injection sublayers, and the mass content of the graphyne in the material of the hole injection sublayer gradually decreases from the direction of the perovskite light-emitting layer to the anode layer.

[0011] Optionally, in some embodiments of the present application, the hole injection layer includes a first hole injection sublayer and a second hole injection sublayer, the second hole injection sublayer is located on a side of the first hole injection sublayer away from the perovskite light-emitting layer, the mass content of graphyne in the first hole injection sublayer is greater than the mass content of graphyne in the second hole injection sublayer, and the energy level difference between the first hole injection sublayer and the perovskite light-emitting layer is greater than the energy level difference between the second hole injection sublayer and the first hole injection sublayer.

[0012] Optionally, in some embodiments of the present application, the material of the first hole injection sublayer is the graphyne, and the material of the second hole injection sublayer is a mixture of the thiophene polymer and the graphyne.

[0013] Optionally, in some embodiments of the present application, the material of the first hole injection sublayer and the material of the second hole injection sublayer are both a mixture of the thiophene polymer and the graphyne.

[0014] Optionally, in some embodiments of the present application, the graphyne includes at least one of α-graphyne, β-graphyne, γ-graphyne, δ-graphyne and 6,6,12-graphyne.

[0015] Optionally, in some embodiments of the present application, the chemical formula of the thiophene polymer is ; wherein n is an integer greater than or equal to 2, and R is an alkyl group.

[0016] Optionally, in some embodiments of the present application, the material of the perovskite light-emitting layer includes one or more of MAPbX3, CsPbX3 and MA(Cs)PbX3; wherein X is a halogen.

[0017] The present application also provides a perovskite light-emitting diode device, which includes:

[0018] cathode layer;

[0019] an anode layer, disposed opposite to the cathode layer; and

[0020] A functional layer, disposed between the cathode layer and the anode layer;

[0021] The functional layer includes a perovskite light-emitting layer and a hole injection layer, the hole injection layer is located between the perovskite light-emitting layer and the anode layer, and the material of the hole injection layer includes a thiophene polymer and graphyne; the hole injection layer includes at least two hole injection sublayers, and the mass content of graphyne in the hole injection sublayer gradually decreases from the direction of the perovskite light-emitting layer to the anode layer; the chemical formula of the thiophene polymer is ; wherein n is an integer greater than or equal to 2, and R is an alkyl group.

[0022] An embodiment of the present application further provides a display panel, which includes a driving substrate and a perovskite light emitting diode device disposed on the driving substrate, wherein the perovskite light emitting diode device is the perovskite light emitting diode device as described in any of the aforementioned embodiments.

[0023] Compared with the perovskite light-emitting diode device in the prior art, in the perovskite light-emitting diode device provided in the present application, the material of the hole injection layer includes a thiophene polymer and graphyne, and due to the π-π interaction formed between the thiophene polymer and graphyne, electron transfer occurs between the thiophene polymer and graphyne. Therefore, the presence of graphyne can reduce the HOMO energy level of the thiophene polymer, thereby improving the hole injection performance of the perovskite light-emitting diode device, so as to improve the luminous efficiency of the perovskite light-emitting diode device. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. The drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 It is a schematic structural diagram of the perovskite light-emitting diode device provided in the first embodiment of the present application.

[0026] Figure 2 It is a schematic diagram of the structure of the perovskite light-emitting diode device provided in the second embodiment of the present application.

[0027] Figure 3 It is a schematic structural diagram of a perovskite light-emitting diode device provided in the third embodiment of the present application.

[0028] Figure 4 It is a schematic diagram of the structure of the display panel provided in this application. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the present application, and are not used to limit the present application. In the present application, unless otherwise stated, the directional words such as "upper" and "lower" used generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the accompanying drawings; while "inside" and "outside" refer to the outline of the device.

[0030] The present application provides a perovskite light emitting diode device and a display panel, which are described in detail below.

[0031] The present application provides a perovskite light-emitting diode device, which includes a cathode layer, an anode layer and a functional layer arranged between the cathode layer and the anode layer; wherein the functional layer includes a perovskite light-emitting layer and a hole injection layer, the hole injection layer is located between the perovskite light-emitting layer and the anode layer, and the material of the hole injection layer includes a thiophene polymer and graphyne.

[0032] Therefore, in the perovskite light-emitting diode device provided in the present application, the material of the hole injection layer includes a thiophene polymer and graphyne, and due to the π-π interaction formed between the thiophene polymer and graphyne, electron transfer occurs between the thiophene polymer and graphyne. Therefore, the presence of graphyne can reduce the HOMO energy level of the thiophene polymer, thereby improving the hole injection performance of the perovskite light-emitting diode device, so as to improve the luminous efficiency of the perovskite light-emitting diode device.

[0033] The perovskite light-emitting diode device provided by the present application is described in detail below through specific embodiments. It should be noted that the description order of the following embodiments is not intended to limit the preferred order of the embodiments.

[0034] It should be noted that the perovskite light emitting diode device in the present application can be bottom-emitting light or top-emitting light. The following embodiments of the present application only take the structure of the bottom-emitting perovskite light emitting diode device as an example for description, but are not limited to this.

[0035] Please refer to Figure 1The first embodiment of the present application provides a perovskite light-emitting diode device 100. The perovskite light-emitting diode device 100 includes a cathode layer 10, an anode layer 20 and a functional layer 30 disposed between the cathode layer 10 and the anode layer 20. The functional layer 30 includes an electron injection layer 31, a perovskite light-emitting layer 32 and a hole injection layer 33. The hole injection layer 33 is located between the perovskite light-emitting layer 32 and the anode layer 20.

[0036] The cathode layer 10 is carried on a substrate (not shown in the figure) to form a cathode substrate (not shown in the figure). The cathode substrate can be a TCO (Transparent Conducting Oxides) substrate, and the TCO can be formed on the substrate by sputtering, photoresist coating, exposure and development, etc. TCO can specifically include one or more of ITO, In2O3, AZO, ZnO, FTO, SnO2, ATO and Sn2O.

[0037] The material of the anode layer 20 may be a transparent conductive oxide. For example, the material of the anode layer 20 may include but is not limited to ITO, IZO and other transparent conductive oxides. Further, the thickness of the anode layer 20 may be 10 nm, 20 nm, 30 nm, 40 nm or 50 nm.

[0038] The material of the electron injection layer 31 may include, but is not limited to, an inorganic material with a lower vacuum level or an organic material with a lower LUMO, or an organic doped material. For example, the material of the electron injection layer 31 may be selected from one or more of alkali metal oxides, alkaline earth metal oxides, alkali metal carbonates, alkaline earth metal carbonates, alkali metal fluorides, alkaline earth metal fluorides, alkaline earth metal hydroxides, and alkali metal hydroxides. In some specific embodiments, the material of the electron injection layer 31 may include one or more of ZnO, LiF, Liq, CaF2, MgF, NaF, KF, BaF2, CsF, CsOH, Cs2CO3, and ZnMgO.

[0039] The material of the perovskite light emitting layer 32 includes one or more of MAPbX3, CsPbX3 and MA(Cs)PbX3, wherein X is a halogen. In some specific embodiments, X is independently selected from one of Cl, Br and I.

[0040] In this embodiment, the material of the hole injection layer 33 includes a thiophene polymer and graphyne. Due to the π-π interaction formed between the thiophene polymer and graphyne, electron transfer occurs between the thiophene polymer and graphyne. Therefore, the presence of graphyne can reduce the HOMO energy level of the thiophene polymer, thereby improving the hole injection performance of the perovskite light-emitting diode device 100, so as to improve the luminous efficiency of the perovskite light-emitting diode device 100.

[0041] In this embodiment, the chemical formula of the thiophene polymer is ; wherein n is an integer greater than or equal to 2, and R is an alkyl group. Since the alkyl chain R at position 3 in the above thiophene polymer can regulate the molecular energy level, the use of the thiophene polymer having the above structure can improve the hole injection performance of the hole injection layer 33.

[0042] Specifically, the alkyl chain R at position 3 of the thiophene polymer can be independently selected from but not limited to butyl (C4H7), pentyl (C5H9) and hexyl (C6H 11 ). Further, as the length of the alkyl chain increases, the HOMO of the thiophene polymer will gradually decrease. In some embodiments, R may also include other non-alkyl substituent groups, and the present application does not specifically limit the type of R.

[0043] The gydne may include at least one of α-gydne, β-gydne, γ-gydne, δ-gydne, and 6,6,12-gydne.

[0044] On the one hand, as a new type of two-dimensional semiconductor material, graphyne has the characteristics of high electrical conductivity; on the other hand, after graphyne is blended with thiophene polymers, due to the π-π interaction between the two, electron transfer will occur between graphyne and thiophene polymers, thereby reducing the HOMO energy level of the thiophene polymer, thereby helping to improve the hole injection performance of the perovskite light-emitting diode device 100.

[0045] It should be noted that, in some embodiments, the functional layer 30 may also include functional film layers such as an electron transport layer and a hole transport layer. The relevant film layer settings may be set according to actual needs, and this application does not limit this.

[0046] Please refer to Figure 2 The second embodiment of the present application provides a perovskite light-emitting diode device 200. The difference between the perovskite light-emitting diode device 200 provided in the second embodiment of the present application and the first embodiment is that the hole injection layer 33 includes at least two hole injection sublayers, and the mass content of graphyne in the material of the hole injection sublayer gradually decreases from the direction of the perovskite light-emitting layer 32 close to the anode layer 20.

[0047] In this embodiment, at least two hole injection sublayers are provided, and the mass content of graphyne in the material of the hole injection sublayer gradually decreases from the perovskite light-emitting layer 32 to the anode layer 20, so as to form a hole injection structure with a graphyne concentration gradient, thereby effectively adjusting the hole injection ability of the hole injection layer 33, thereby further improving the hole injection performance of the hole injection layer 33, and further improving the luminous efficiency of the perovskite light-emitting diode device 200.

[0048] It should be noted that the number of hole injection sublayers in the present application can be two, three or more than three. This embodiment is only described by taking the number of hole injection sublayers as two as an example, but is not limited to this.

[0049] Specifically, the hole injection layer 33 includes a first hole injection sublayer 331 and a second hole injection sublayer 332. The second hole injection sublayer 332 is located on a side of the first hole injection sublayer 331 away from the perovskite light emitting layer 32.

[0050] The mass content of graphyne in the hole injection sublayer 331 is greater than the mass content of graphyne in the second hole injection sublayer 332. The energy level difference between the first hole injection sublayer 331 and the perovskite light-emitting layer 32 is greater than the energy level difference between the second hole injection sublayer 332 and the first hole injection sublayer 331. Thus, by forming hole injection sublayers with different graphyne concentrations, the energy level difference between the perovskite light-emitting layer 32 and the first hole injection sublayer 331 is greater than the energy level difference between the first hole injection sublayer 331 and the second hole injection sublayer 332, thereby generating an energy level difference between the film layers in a bottom-up direction, thereby being able to effectively regulate the energy level difference between the hole injection layer 33 and the perovskite light-emitting layer 32, improve the hole injection performance of the device, and further improve the luminous efficiency of the perovskite light-emitting diode device 200.

[0051] In this embodiment, the material of the first hole injection sublayer 331 and the material of the second hole injection sublayer 332 are both a mixture of thiophene polymer and graphyne.

[0052] Please refer to Figure 3 The third embodiment of the present application provides a perovskite light-emitting diode device 300. The difference between the perovskite light-emitting diode device 300 provided in the third embodiment of the present application and the first embodiment is that the material of the first hole injection sublayer 331 is graphyne, and the material of the second hole injection sublayer 33 is a mixture of thiophene polymer and graphyne.

[0053] Please refer to Figure 4, the present application also provides a display panel 1000. Among them, the display panel 1000 can be an organic light emitting diode display panel. Specifically, the display panel 1000 includes a driving substrate 101 and a light emitting layer 102 arranged on the driving substrate 101. The light emitting layer 102 includes a plurality of perovskite light emitting diode devices (not shown in the figure). Among them, the perovskite light emitting diode device can be the perovskite light emitting diode device described in any of the aforementioned embodiments, and the specific structure of the perovskite light emitting diode device can refer to the description of any of the aforementioned embodiments, which will not be repeated here. In addition, the structure of the driving substrate 101 is a prior art and will not be repeated here.

[0054] The above is a detailed introduction to a perovskite light-emitting diode device and a display panel provided in the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A perovskite light-emitting diode device, characterized in that: include: cathode layer; an anode layer, arranged opposite to the cathode layer; as well as A functional layer, disposed between the cathode layer and the anode layer; Wherein, the functional layer comprises a perovskite light-emitting layer and a hole injection layer, the hole injection layer is located between the perovskite light-emitting layer and the anode layer, and the material of the hole injection layer comprises a thiophene polymer and graphyne; The hole injection layer includes a first hole injection sublayer and a second hole injection sublayer, the second hole injection sublayer is located on a side of the first hole injection sublayer away from the perovskite light-emitting layer, the mass content of graphyne in the first hole injection sublayer is greater than the mass content of graphyne in the second hole injection sublayer, and the energy level difference between the first hole injection sublayer and the perovskite light-emitting layer is greater than the energy level difference between the second hole injection sublayer and the first hole injection sublayer; the material of the first hole injection sublayer is the graphyne, and the material of the second hole injection sublayer is a mixture of the thiophene polymer and the graphyne.

2. The perovskite light-emitting diode device according to claim 1, characterized in that: The gyne includes at least one of α-gyne, β-gyne, γ-gyne, δ-gyne and 6,6,12-gyne.

3. The perovskite light-emitting diode device according to claim 1, characterized in that: The chemical formula of the thiophene polymer is: wherein n is an integer greater than or equal to 2, and R is an alkyl group.

4. The perovskite light-emitting diode device according to claim 1, characterized in that: The material of the perovskite light-emitting layer includes one or more of MAPbX3, CsPbX3 and MA(Cs)PbX3; wherein X is a halogen.

5. A perovskite light-emitting diode device, characterized in that: include: cathode layer; an anode layer, arranged opposite to the cathode layer; as well as A functional layer, disposed between the cathode layer and the anode layer; The functional layer includes a perovskite light-emitting layer and a hole injection layer, the hole injection layer is located between the perovskite light-emitting layer and the anode layer, and the material of the hole injection layer includes a thiophene polymer and graphyne; the hole injection layer includes at least two hole injection sublayers, and the mass content of graphyne in the hole injection sublayer gradually decreases from the direction of the perovskite light-emitting layer to the anode layer; the chemical formula of the thiophene polymer is; wherein n is an integer greater than or equal to 2, and R is an alkyl group; The hole injection layer includes a first hole injection sublayer and a second hole injection sublayer, the second hole injection sublayer is located on a side of the first hole injection sublayer away from the perovskite light-emitting layer, the mass content of graphyne in the first hole injection sublayer is greater than the mass content of graphyne in the second hole injection sublayer, and the energy level difference between the first hole injection sublayer and the perovskite light-emitting layer is greater than the energy level difference between the second hole injection sublayer and the first hole injection sublayer; the material of the first hole injection sublayer is the graphyne, and the material of the second hole injection sublayer is a mixture of the thiophene polymer and the graphyne.

6. A display panel, characterized in that: It comprises a driving substrate and a perovskite light emitting diode device arranged on the driving substrate, wherein the perovskite light emitting diode device is the perovskite light emitting diode device according to any one of claims 1 to 5.

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